Different strategies for producing soluble form of natural common cytokine receptor gamma chain

Authors: JEONG, JIPSEOL - Gyeongsang National University; KIM, WOO - Gyeongsang National University; KIM, SUK - Gyeongsang National University; Lillehoj, Hyun; WOO, HEE-JONG - Seoul National University; MIN, WONGI - Gyeongsang National University

Submitted to: Developmental and Comparative Immunology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/19/2014
Publication Date: 8/27/2014
Publication URL: http://handle.nal.usda.gov/10113/61087
Citation: Jeong, J., Kim, W.H., Kim, S., Lillehoj, H.S., Woo, H., Min, W. 2014. Different strategies for producing soluble form of natural common cytokine receptor gamma chain. Developmental and Comparative Immunology. 48(1):13-21.

Interpretive Summary: Limited understanding of various immune components of poultry hinders the progress with basic understanding of how various immune factors work to protect against infectious diseases in poultry. In chickens many lymphocyte-produced proteins share a recetor called common receptor ' chain ('c) which is expressed on many cell types of lymphocyte origin. These receptors transmit signals for immune response which ultimately relates to crucial regulation of lymphocyte development, proliferation, and homeostasis. However, there has been no information on how these 'c receptors play roles in regulating their biological activities in poultry mainly because of the difficulty in isolating this molecule. In this paper, ARS scientists collaborated with scientists at a South Korean university to successfully develop a new method of isolating chicken common receptor proteins. Thus, many questions concerning the role of this protein in host immune repsonse in poultry can now be investigated. This discovery will enhance our fundamental understaidng of chicken immune system and the function of lymphocyte receptor molecule.

Technical Abstract: The common cytokine receptor ' chain ('c) plays an essential role in regulating lymphoid homeostasis and alterations in its structure causes severe immunodeficient diseases. Although soluble 'c (s'c) was first reported in the late 1990's, many questions still remain unanswered concerning the shedding mechanism of s'c. The ability to produce soluble isoforms of 'c from different animal species will enable basic research towards a better definition of the immunological function of s'c. In this study, we describe various strategies for producing soluble isoforms of 'c in different species. Mouse 'c and the avian ortholog, 'c-a, did not produce s'c. In mice, two 'c isoforms, CRA-a and m'c-b, which are encoded by transcripts lacking a transmembrane region by alternative splicing, are mainly detected in cell lysates. However, ducks produce s'c from 'c-b transcript lacking a transmembrane region by alternative splicing. In chickens, s'c was produced by proteolytic shedding of the 'c-b isoform containing the intron 5, which dramatically increased the probability of proteolytic cleavage of the ectodomain and produced s'c in normal cells and several established chicken cell lines. This shedding was suppressed by protease inhibitors. Intracellular fragments of 'c-b were found predominantly inside the cell, with a low level detected within the nucleus. Compared to the chicken ortholog 'c-a, the expression of 'c-b mRNA was differentially regulated according to the type of tissue, developmental stage and the nature of activating antigens. These results demonstrate different cellular mechanismsof generating s'c, and its potential role in maintaining lymphoid homeostasis in response to environmental antigens in avian species.